JP4717034B2 - Electromagnetic safety valve - Google Patents

Description

  The present invention relates to an electromagnetic safety valve that is opened in a gas passage and closes the gas passage in a predetermined case to prevent gas leakage and the like.

  For example, a gas supply pipe which is a gas passage for supplying gas is connected to the gas burner. There is a case where a thermal power adjusting device for adjusting the thermal power is provided in the gas supply pipe, but an electromagnetic safety valve is further provided on the upstream side. This electromagnetic safety valve is for preventing the unburned gas from being discharged from the gas burner with the gas passage closed when, for example, the gas burner misfires during combustion or an ignition failure occurs during ignition.

  Many such electromagnetic safety valves have been proposed in the past. For example, a U-shaped fixed iron core is held by a metal holder, and a coil wound around a bobbin is placed on one of a pair of magnetic poles of the fixed iron core. The thing to wear is known (for example, refer to patent documents 1).

  In this device, one end of the coil is connected to the holder, and the other end is connected to a terminal made of a wire. This terminal extends to the outside through a through hole provided in the bottom of the holder. However, in this state, the through hole is not sealed, and the gas leaks outside through the through hole. Therefore, the sealed pipe is attached to the holder, a terminal is passed through the pipe, and then the tip of the pipe and the tip of the terminal are joined airtightly by welding or the like to seal the through hole.

In addition, although the bobbin is attached to one magnetic pole in what was described in the said patent document 1, in such a structure, the length of a magnetic pole becomes long and an electromagnetic safety valve may enlarge. In view of this, there has been known a device in which a bobbin is attached to a substantially central portion of a fixed iron core to shorten the magnetic pole length (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 2000-18591 (FIGS. 1 and 2) Japanese Patent Laying-Open No. 2005-110385 (FIG. 3)

  In the conventional electromagnetic safety valve, one end of the coil is connected to the holder, and welding or soldering is used for the connection. For this reason, there may be a case where it is visually connected, but it may not be electrically connected. To ensure the connection, the connection work becomes complicated, and if a connection failure occurs, the product is defective. It becomes.

  Moreover, although the airtightness is ensured by mutually welding the terminal which consists of a wire, and a pipe, the malfunction that it is difficult to ensure the reliability of the airtightness in the welding part also arises.

  In addition, in what is described in Patent Document 2, since the bobbin is attached to the substantially central portion of the fixed iron core, when the fixed iron core is stored in the holder, the fixed iron core can be brought into direct contact with the bottom of the holder. The fixed iron core is held by the holder via the bobbin. Then, the stress when the movable iron piece is pressed against the fixed iron core acts on the holder via the bobbin.

  Since the bobbin is generally made of resin, when such a stress acts on the bobbin, the bobbin is deformed, the posture of the fixed iron core is shifted, and there is a problem that the movable iron piece cannot be reliably attracted.

  Then, this invention makes it a subject to provide the electromagnetic safety valve which does not produce the above-mentioned malfunction in view of said problem.

In order to solve the above-described problems, an electromagnetic safety valve according to the present invention includes an electromagnet including a U-shaped fixed iron core, a bobbin attached to the fixed iron core, and a coil wound around the bobbin in a holder, and a gas passage. A pair of terminals connected to a coil in an electromagnetic safety valve that has a valve body that opens and closes and a movable iron piece coupled to the valve body, and that holds the valve body in an open state by adsorbing the movable iron piece to a fixed iron core The rod is held by the bobbin, and a pair of through holes are formed in the bottom of the holder. The terminal rod is inserted into the through hole and the tip of the terminal rod is exposed to the outside. By sealing the through hole at the bottom of the holder with a sealing member attached from the front end side , the terminal rod is fixed to the holder, and the bobbin connected to the terminal rod prevents the fixed iron core from falling off the holder. The The bobbin is attached to the substantially central part of the fixed iron core, and the fixed iron core is brought into contact with the holder so that the stress at the time when the movable iron piece is pressed against the fixed iron core is received by the contact part. Features.

  Conventionally, at least one end of the coil is connected to the holder, but in the above configuration, the bobbin holds a pair of terminal rods, so that both ends of the coil can be connected to the terminal rods respectively. Can be performed at a stage before the bobbin is attached or at a stage before the fixed iron core is held by the holder.

  A bobbin is attached to the substantially central portion of the fixed iron core, the fixed iron core is brought into contact with the holder, and the stress when the movable iron piece is pressed against the fixed iron core is received by the contact portion. For example, when the movable iron piece is pressed against the fixed iron core, the bobbin is not deformed and the posture of the fixed iron core is not shifted.

  As apparent from the above description, the present invention can connect the coil to both terminal rods in advance before attaching the bobbin to the fixed iron core or holding the fixed iron core on the holder. Connection with the terminal rod can be performed reliably and stably.

    Referring to FIG. 1, 1 is an example of an electromagnetic safety valve according to the present invention. The electromagnetic safety valve 1 includes a bottomed holder 2 that opens upward, and a fixed iron core 3 is held inside the holder 2. The fixed iron core 3 is made of a magnetic material and is formed in a substantially U shape. The bobbin 4 is attached to one of the pair of magnetic poles 31 of the fixed iron core 3. The bobbin 4 is made of resin, and a coil 41 is wound around it. A pair of terminal rods 5 are held on the bobbin 4, and both ends of the coil 41 are electrically connected to the terminal rods 5 respectively.

  Therefore, when the coil 41 is energized from the outside via the terminal bar 5, the fixed iron core 3 is excited by the magnetic field generated by the coil 41. A movable iron piece 13 connected to the valve element 11 is provided above the fixed iron core 3, and the valve element 11 is pushed downward against the urging force of the spring 12, thereby moving the movable iron piece 13 to the fixed iron core 3. When pressed against the magnetic pole 31, the movable iron piece 13 is attracted to the fixed iron core 3, and the valve body 11 is held in the valve open state. Note that if the energization of the coil 41 is stopped, the fixed iron core 3 is not excited, so that the attractive force acting on the movable iron piece 13 disappears. As a result, the valve body 11 is pushed upward by the urging force of the spring 12 to be closed.

  With reference to FIG. 2, in this embodiment, when the bobbin 4 is injection-molded, both terminal bars 5 are cast into the bobbin 4 and the both terminal bars 5 are fixed to the bobbin 4. Then, when the coil 41 is wound around the bobbin 4, both ends of the coil 41 are wound around the connection portions 51 to be electrically connected.

  In this manner, the bobbin 4 is mounted on one magnetic pole 31 from above with the coil 41 wound around the bobbin 4 and being sub-assembled.

  With reference to FIG. 3, a through hole 21 into which the terminal rod 5 is inserted is formed at the bottom of the holder 2, and the tip of the terminal rod 5 projects outside through the through hole 21. In this state, the rubber packing 6 was attached to the terminal bar 5 from below so as to hermetically seal the through hole 21. Then, the cover 14 is attached to the holder 2 so that the packing 6 does not fall off, and the packing 6 is always pressed against the through hole 21.

  In the embodiment shown in FIGS. 1 to 3, the bobbin 4 is mounted on one magnetic pole 31. However, in such a configuration, the vertical dimension of the fixed iron core 3 becomes long, and the mounting location of the electromagnetic safety valve 1 is increased. Depending on the situation, inconvenience may occur.

  Therefore, as shown in FIG. 4, the bobbin 4 ′ can be attached to the connecting portions 32 ′ at both center portions sandwiched between the magnetic poles 31 ′ of the fixed iron core 3 ′. The bobbin 4 'is divided into two parts on the left and right, and the coil 41 is wound in a state of being joined from both the left and right sides so as to sandwich the connecting part 32'. Note that the terminal rod 5 is fixed to both bobbins 4 'in advance, and after the coil 41 is wound, both ends of the coil 41 are connected to the terminal rod 5, respectively, as shown in FIG. 4B. Keep assembled.

  Next, as shown in FIG. 5, the bobbin 4 'and the coil 41 are set in the holder 2' together with the fixed core 3 'in the holder 2'. A through hole 21 'similar to that described above is formed at the bottom of the holder 2', and the terminal rod 5 projects outside through the through hole 21 '. Then, the packing 6 was attached to the terminal bar 5 in the same manner as described above, and the packing 6 was pressed by the cover 14.

  By the way, the fixed iron core 3 'is engaged with the holder 2' at the engaging portion shown in A, and even if the movable iron piece 13 is strongly pressed against the fixed iron core 3 ', the stress is received by the engaging portion A. I did it. Therefore, the bobbin 4 'does not come into contact with the holder 2', and therefore the bobbin 4 'is not deformed by this stress.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

The figure which shows the structure of one embodiment of this invention The figure which shows the assembly state in 1st Embodiment Sectional drawing which shows the structure in 1st Embodiment The figure which shows the assembly state in 2nd Embodiment Sectional drawing which shows the structure in 2nd Embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electromagnetic safety valve 2 Holder 3 Fixed iron core 4 Bobbin 5 Terminal rod 6 Packing 11 Valve body 13 Movable iron piece 14 Cover 21 Through-hole 31 Magnetic pole 41 Coil

Claims (1)

The holder includes an electromagnet including a U-shaped fixed iron core, a bobbin attached to the fixed iron core, and a coil wound around the bobbin, and a valve body that opens and closes a gas passage, and a movable body connected to the valve body. In an electromagnetic safety valve having an iron piece and adsorbing a movable iron piece to a fixed iron core to hold the valve element in a valve-opened state, a pair of terminal rods connected to a coil are held by the bobbin and at the bottom of the holder A pair of through-holes are formed, and the terminal rod is inserted into the through-hole and the tip of the terminal rod is exposed to the outside. With the sealing member attached from the tip of the terminal rod, the through-hole at the bottom of the holder When the terminal core is fixed to the holder by hermetically sealing the bobbin connected to the terminal bar to prevent the fixed iron core from falling off the holder , and when the bobbin is attached to the substantially central portion of the fixed iron core Both The stationary core is brought into contact with the holder, the electromagnetic safety valve, characterized in that the stress generated when the movable iron piece is pressed against the fixed iron core, and to receive at its contact portion.

Images